Many buses struck tunnels in Stockholm lately

[Bobjork]

I don't know why (Maybe a lot of summer extras), but lately buses have struck the Klara tunnel i Stockholm. It has happened earlier too, despite more and more safety features and signs.
This morning an empty coach from Traveller entered the 3.0m Klara tunnel. His bus was decabbed and a motorcyclist behind crashed with the bus or parts of it.
Both driver was sent to hospital with minor injuries.
http://www.aftonbladet.se/nyheter/article20987554.ab
http://www.expressen.se/nyheter/buss...-klaratunneln/
http://sverigesradio.se/sida/artikel...rtikel=6193286

On monday 16/6 an articulated bus almost got stuck in the tunnel. It managed to stop before reaching the tunnel but was unable to reverse away because it was stuck in the ramp before. The bus was on its way to Lidingö to be used by Stockholm spårvägar as replacement service for the light rail.
http://www.aftonbladet.se/nyheter/article20976159.ab

13/6 a CNG-bus crashed into the tunnel, but the tanks we're not detached like the last time that happened (june 2013).

8/6 a bus from Westin Bus struck the entrance to the tunnel from Centralbron down to Slussen. This driver managed to stop before it got completely stuck. Also, he made two mistakes: Bus was to high plus it was longer than the maximum permitted 12 meters in that tunnel (sharp bend).